Ripening pineapple fruit is susceptible to infection by a variety of disease-causing microorganisms. Such diseases tend to develop and damage the fruit during fruit maturation starting from 20 days before the fruits are harvested until they reach the consumer as fresh fruit or are processed in the cannery as canned pineapple. Thus, the internal quality of fresh fruit is reduced and fruit solid recovery in the cannery may be significantly decreased due to attack by such microorganisms as Acetomonas sp., and Erwinia herbicola, which are believed to cause pineapple pink disease. Other deteriorating pineapple diseases resulting from microbial action include marbling, which is believed to be caused by species of Acetobacter. and fruitlet-core rot (black spot), which is is believed to be caused by a complex of microorganisms such as Penicillium sp., and Fusarium sp., bacteria, and yeasts.
It is known in the art that the deterioration of fruit by microbial action, e.g. fungus or bacterial growth, can be inhibited by subjecting the fruit after harvesting to an atmosphere having a low oxygen and high carbon dioxide content. See, A. A. Kader, M. A. El-Govrani, and N. F. Sommer, Effect of CO+ Elevated CO.sub.2 and/or Reduced O.sub.2 Levels on Postharvest Behavior and Quality of Peaches, Vol. 14(3) Hort Science (1979), p. 471.
Accordingly, efforts have been made to create a micro-environment which is unfavorable for the growth of fruit microorganisms, for example, by applying a coating of wax to the surface of the harvested fruit. However, the use of wax is often objectionable from a consumer standpoint, because the color, texture, or flavor of the fruit is often undesirably effected by the wax coating. Additionally, it is difficult to apply such wax coatings evenly over the surface of the fruit without using so much wax that the normal "breathing" of the fruit is interfered with to an undesirable extent.